Non-destructive inspection (NDI) of the parts of an engine enables the state of those parts to be verified without degrading them. Non-destructive inspection techniques include in particular penetrant inspection, magnetoscopy, detecting eddy currents, ultrasound detection, etc.
With a turbomachine engine, it is preferable for inspections to be performed directly on the engine while it is mounted under the wing of an airplane so as to avoid removing the engine and disassembling it at least in part in order to access the parts for inspection. In situ inspection of parts serves to limit the down time of the airplane, and is less expensive. There therefore exists a need for tools that are well adapted to non-destructive in situ inspection of parts of a turbomachine motor of a given type.
The parts for inspection in a turbomachine engine are often situated in zones that are difficult to access by conventional inspection tools. It is necessary to test these tools under real conditions, i.e. on an operational engine, in order to develop the tools, in particular as a function of the environment that is specific to the parts for inspection, and also in order to calibrate the tools.
In the present technique, it is possible to use a digital model of the engine to simulate passing an inspection tool through access orifices and/or passages of the engine until a distal end of the tool is situated at a part for inspection. Nevertheless, that solution does not make it possible to take account of all of the problems associated with the environment of the engine parts, so it is necessary to repeat the test on an operational engine in order to validate the tool. The discovery of problems or difficulties that were not observed beforehand leads to delays in developing the tool and can even lead to certain types of inspection of the part under question being abandoned.
One solution to that problem would be to fabricate a portion of an operational engine solely for the purpose of developing tools for inspecting parts in said engine portion. Nevertheless, the real parts needed are not always available and the cost of such a technique would be prohibitive. It is also possible to envisage making said engine portion out of parts that have been rejected, thereby reducing the cost of fabrication. Nevertheless, that would make it necessary for said engine portion to be made only after engine design and construction had taken place, thereby making it necessary to test and develop inspection tools after such engines have been built, and that presents many drawbacks.
On the contrary, it is desirable for inspection tools to be developed in parallel with the design and construction of the first engines that are to be sold, in such a manner that the non-destructive inspection of parts of said engines can be defined and made available to the purchasers of engines with it being guaranteed that they will function properly.